2014 Ram 2500 6.7 Cummins won’t start or preheat

[Joe Schulte]

Hey all,

Frustrated with my current situation. 2014 ram 2500 6.7 Cummins will not start. I put the key fob turn to start preheat... doesn’t preheat, the rest of the dash is reading incorrectly.. says it’s -47 degrees saying tires are flat etc. I then go to try and start it but it’s one click and won’t start. Batteries? Computer? Not sure and thought I’d ask.

 

[mtnrider]

Dead batteries, pretty common, they don't last forever. Get them load tested but 99.9% sure that is your issue so don't get too panicked.


.

 

[Joe Schulte]

I appreciate it!

 

[Joe Schulte]

I’m just confused because all interior electronics work normally, windows aren’t sluggish, head lights look normal. I’m going to get the batteries load tested but it’s odd to me when the truck was running perfectly yesterday, all day.

 

[MADDOG]

Internal power requirements are a lot lower than the CCA's needed to turn over that Cummins.

Those weird readings are indicative of a low power issue. Test your batteries and make sure all your grounds are clean and tight, free of dirt and corrosion.

 

[crash68]

The grid heater draws lots of current, and it's possible you lost a cell or two in the batteries.
Also check the wiring harnesses that are under the truck, inside the frame rail on the driver's side.

 

[Ltngdrvr]

Definitely a battery issue, probably at least one is bad.
And, remember that to do a proper load test, at least one battery needs to be disconnected from the truck since the batteries are interconnected and will cause a false reading if tested while both are still connected.
And, when you find the bad battery, replace BOTH, or the old battery will go bad soon and pull the new one down.

 

[Gr8bawana]

I also suspect batteries, hopefully the OP will check back with us and let us know the outcome.

 

[BubbaJo]

Internal power requirements are a lot lower than the CCA's needed to turn over that Cummins.

Those weird readings are indicative of a low power issue. Test your batteries and make sure all your grounds are clean and tight, free of dirt and corrosion.

THIS

Diesels require a lot of juice to start, especially on colder mornings. So much so that if you leave your truck plugged in constantly every night, all night, for a month straight, you WILL see a noticeable increase in your electric bill

 

[chri5k]

The CTD trucks seem to be sensitive to batteries probably due to the high starting current requirement. Once my truck starts cranking a bit slower than usual, I replace the batteries. If it takes more than 2 - 3 seconds of cranking to start, I consider that slow. It seems batteries these days start cranking a tad bit slower and then suddenly die. They usually test "good" at the store but I replace them anyway. Since they test "good" I usually miss out on the the pro-rata refund but such is life.

 

[Ltngdrvr]

Have never had mine crank "slow", it either cranks or doesn't.
ECM controls the starter, and if it doesn't see a proper battery status it won't engage the starter.
I sleep in my truck often when on the road, and run a fan during warm weather, and have run the batteries down during the night resulting in a no-crank situation. I carry a pair of Li-On battery jumpers, one for each battery, and they make it crank right away whenever this happens.
I bought the jumpers when I had a battery go bad, and they even allowed me to start the truck at that time.